Fixes broken group specs on MySQL

What does this MR do?

Related to https://gitlab.com/gitlab-org/gitlab-ee/issues/12227, fixes the following failures:

• https://gitlab.com/gitlab-org/gitlab-ee/-/jobs/232990602
• https://gitlab.com/gitlab-org/gitlab-ee/-/jobs/232990604

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers

Closes #12227 (closed)